Ribbed or corrugated sheet-metal member



Sept. 11, 1928.

' 1,683,841 J. J. MULLEN ET AL RIBBED on CORRUGATED SHEET METAL MEMBER.

Filed Jan. 7, 1927 III III

.l/ VEN T 0 E5 .J ame; J Mu//en.

ans/5 fly 5 container, can

Patented Sept. 11, 1928.

JAMES J. MULLEN AND FRANCIS M. S'IlAMIBAUG-H,

T oFFicE.

OF ST. LOUIS, MISSOURI; SAID STAMBAUGH ASSIGNOR TO SAID MULLEN.

RIBBEI) 0R CORRUGATED SHEET-METAL MEMBER.

Application filed January 7, 1927. Serial No. 159,587.

This invention relates to sheet metal members of the type that comprisestraight corrugations or folded portions of the plate from which the 5member is constructed, one example of such sheet metal members beingcontainers that are used as tanks or cases for transformers,-

which are submerged in oil.

Such containers comprise a sheet metal side wall provided withlongitudinally-disposed ribs or corrugations and various methods havebeen resorted to for closing the ends of the ribs. In one type ofconstruction that has been used extensively, the corrugations extendthroughout the entire length of the plate used to form the side wall andcast metal members are cast onto the end portions of said plate after ithas been bent into the shape desired for the side Wall, so as to closethe ends of the corrugations andalso form the top and bottom of thecontainer, but the objections to such a container are that it isextremely heavy and bulky; it is expensive to manufacture, and thejoints between the side wall and the east end pieces "are apt to leak.

struction the corrugations on the side wall plate are flattened ormashed down at the end portions of the side wall and metal is to addedto the, flattened portions of the cor-.

rugations, usually by a welding operation, so as to obtain plain runs orhands at the opposite ends of the side wall to which the.

end members, i. e., top and bottom ofthe be attached, but suchaconstruction is objectionable, in that it looks crude; it is expensiveto manufacture and the end portions of the side wall comprise numerousthicknesses of metal. In another type of construction slits are formedin the corrugations in the end portions of the side wall and the slittedportions of said wall then folded or bent into overlapping relation,with a view to obtaining rims or bands at the ends of the side wall towhich the end members can be attached, but such a construction is alsoof crude appearanceiand is very expensive to manufacture, on account ofthe relatively great. amount of welding that is required to close theslits in the end portions of the side wall and build up sufiicient metalon same to producefairly smooth surfaced bands or rims to which the endmembers can e, a a h d, It still anather hollow ribs formed by bent orIn another type of con- 'form the top and bottom of type of constructionthe plate which constitutes the side wall of the container is notchedout at its ends, the intermediate portions of the plate lying betweenthen bent orfolded so as to lVhile such a construction produces acontainerthat presentsa mechanical-like appearance,- the cost. offitting closures in both ends of each corrugation and then producin awelded joint around the entire edge of eacli of said closures makes thistype of construction practically prohibitive toruse as a tank or casefor transformers.

One object of our invention is to provide a sheetm'etal container of thegeneral type previously mentioned, i. e., one havin a r bbed orcorrugated side wall that is r3121 tively inexpensive to manufacture;that presents a neat and mechanical-like appearance, of'such design thatit is a slim ple matter to produce liquid-tight joints between the endportions of the side. wall and the end members that constitute the topand submerged in oil or other liquid but we wish it to be understoodthat our broad idea isapphcable to various typesand kinds of sheet metalmembers used for other purposes.

When our invention is embodied in a transformer tank or case, as hereinillustrated, the side wall of the tank with a plurality of corrugationsor hollow ribs that terminate short of the ends of are closed. at bothends by integral portions of the plate from which the side wall istormed, the end portions of the side wall beis provided yond the ends ofsaid corrugations constitut ing rigid, plain uncorrugated bands that areformed by end merge into plain portions of the wall that lie between thecorrugations. Any preferred type or kind of end mem'bers'canibe used tothe tank, but we prefer to use flangedcnd platesthat are 0onlongitudinally-disposed said side wall and which sections of the platethat said notches are I On welding or in any other nected by rivets,

the end portions of the designates thes'de'wall ofa transformer tanker:case which n'1ay be oblong, oval or side wall and secured tosame of anyother preferred cross-sectional shape andzeonstrurtcd from one or aplurality of metaliplates, B: designates the end members that constitutethe top and bottom of said tank, and C designateslongitudinally-disposed corrugations or hollow ribs on the side wall A.In such a container the corrugations '0 increase the area of the sidewall thatispresented to the air wh ch circulates over the eontainer, andthus, in eiiect, act asradiating fins which absorb heat from the oil orother liquid inside of the container that is used to cool thetransformer which the container houses, but, as previously stated, it isimmaterial what funct on is performed by the corrugations C gations Cmay vary in nnmbergin dimen sions and in arrangement, and in addition toincreasing the 'adiating surface of the side wall oii the tank, saidcorrugations also act to reinforce and stiffen the side wall.

As shown; in: the drawings, the corrugations C terminate shortof the topand hottoinedges ofthe side wall A, and the end Y plain or unend bandsor rims to which the end members B are attached, preferably by flanges 1on said. end-members arranged either on the inside or on the outside ofthe end rims of the by riveting, welding or in any other suitablemanner. The corrugations G are provided at their ends with closuresformed by integral portions of the-plate fromwhich the sidewallisconstructed, and while said end closures can be formed in various wayswithout departing from the spirit of ourinvention, it is preferable toprovide the side portions 2 of the corrugations with angularly-disposed,integral extensions 3 that merge into the end sections of theplate thatconstitute the end bands or rimslto which the top and bottom oflthetanlr are attached.

In the operation-ofconstruction the side wall A. of the tank,longitudinal l y-aligned notches are formed in-the opposite ends of thea platerwhich constitutes said side wall at The corru-' the points wherecorrugations are to be formed, prior to the operation of, bending orfoldin said plate to produce the corrugation. 'lhe metal at the innerends of said notches is also preferably bent; and by a combined bendingand drawing operation, so as to produce the angularly-disposed portions,3 previously referred to, that constitute the end closures for thecorrugations, it being preferable to form disposed portions 3 at theinner end of each notch that increase gradually in depth or height fromthe center towards the side edges notch and which are drawn orstretchcdslightly at the points merge into the end sections 4 of theplate which lie between adjacent notches. 'll1ereafter, when theintermediate portions of the; plate lying in longitudinal alignment withsa d. end notches isbent or the corrugation C, the two laterally-bentportions 3 at the inner end of each notch come together into abuttingrelationship, and thus co-opcrate to form a closure for one end; of thecorrugation that is disposed at an angle and integrally connectedto therim or plain end portion of the side wall located beyond the endof thecorru ation. In the operation of folding or bending the intermediateportion of the plate to produce a corrugation C, the adjacentendsections 4 0f the plate lying at opposite sides of the notch in theend of the plate cometogether or move into substantially abutting relatonship, as showirin Figure each other to form part of the rim, bandoruncorrugated end portion of the side wall, said end sections l lying inthe same plane and merging'into plain portions of the wall that lie atopposite sides of the corrugation,

thereby forming very rigid end bands. Subsequently, the joint 5 betweensaid end sections el and the joint between the angularlydisposedportions 3, are closed by a continuous seam (5, produced by asoldcringyllfi welding or brazing operation. said scams 6 also tendingto stiffen the endr m of the side wall* formed by the end sections l ofthe platewhich are not subjected to a. bending or deforming operationwhich weaken the same. \Ve make no claim herein to the method ofconstructing the container or to the apparatus used in the operation ofbendin or-folding the intermediate portions of" the plate thatconstitute the corrugations 12 or ribs. as said method forms thesubjectmatter of our pending application for patent Serial No. 159,588,filed J an. 7, 1927, and said apparatus forms the subject-matter of ourpending application Serial No. 159,589, filed 121 Jan-7,1927. a

While we prefer to form the end closure of each corrugation C by twolaterally-pro jecting' extensions 3 on the side portions 2? ofthecorrugation that are joined together 13 shaped 7 two angularly- 75 3where they folded to produce 35 2, and thus co-operate with 1 tends towall have been closed by a seam 6 located at the longitudinal axis ofthe corrugation, we wish it to be understood that the end closures ofthe corrugations can be formed in various other ways without departingfrom the spirit of our invention. The essential thing isthat the ends ofthe corrugations be closed by integral portions of the plate or platesof which the corrugations form a part,the particular shape of saidintegral portions being immaterial and the particular location of thescams or joints in the end closures and in the end portions of the platebeing immaterial, so long as the side wall of the container is providedwith integral, laterally-projecting corrugations provided with closedends formed by integral portions 'of the plate, and arranged betweenplain or uncorrugated rims at the ends of said wall that are formed byend sections of the plate that lie in the same plane and merge intoplain portions of the wall located between the corrugations. After thejoints in corrugations and in. the end rims of the side or seamed, saidwall will be just as tight and will present practically the sameappearance as a wallprovided with corrugations or hollow ribs producedby a drawing operation. In other words, a sheet metal member orreceptacle of the construction above described can be manufactured at afraction of thecost of a mem her having end rims and provided withhollow ribs or corrugations that are produced by a drawing operation,because the end rims of my improved member or receptacle are formed bysubstantially straight or flat end sections of the plate, and thecorrugations C and the parts of the plate that constitute closures forthe ends of said corrugations are formed by a simple bending operation,followed by a seaming operation that is relatively inexpensive, onaccount of the short length of the joint-s in the end 010 sures of thecorrugations and between the end sections of the plate located beyondthe ends of the corrugations. This, coupled with the fact that the sidewall is absolutely liquid-tight throughout its entire area and isprovided with rigid end bands comprising a single thickness of metal towhich end members can be easily attached, makes such a receptacleparticularly well adapted for use as a transformer tank or case. viouslystated, however, our invention is not restricted to a container orreceptacle, but is applicable to any kind of a sheet metal memberprovided with a closed end corrugation o o w rib the end closures of thegations, a rim atone As preour invention, what deslre' to secure byHaving thus described we claim as new and Letters Patent is:

lfA sheet metal member having a side Wall provided with laterallyprojecting ribs, or hollow corrugations, formed by folded or bentportions of the plate from which said receptacle is constructed, endclosures for said corrugations formed by integral portions of saidplate, and a rim located beyond one end of said corrugations and formedby abutting end sections of said plate that merge into the portions ofthe side wall located between said corrugations.

2. A sheet metal receptacle provided with end rims formed by abuttingend sections of the plate from which said receptacle is constructed,laterally-projecting corrugations or hollow ribs on the side wall ofsaid receptacle located between said rims and formed by bent or foldedportions of the plate, and

end closures for said corrugations formed by integral extensions thecorrugations arranged in abutting relationship and joined together byseams which extend across said rims between the abutting end sections ofthe rims.

3. A sheet metal'receptacle, comprising a side wall provided withlaterally-projecting corrugations and flat portions between saidcorrugations, said corrugations being formed by bent or folded portionsof the plate from which said side wall is constructed, end closures forsaid corrugations formed by integral bent portions of said plate thatare joined together by seams, and a rim at one edge of said side wallformed by abutting end sections of said plate that are joined togetherby seams located in alignment with said corrugations. v

4. A sheet metal receptacle having a side wall provided withlaterally-projecting corrugations or hollow folded portions of the platefrom which said receptacle is constructed, closures for one end ofsaidcorrugations formed by integral extensions on the side portions ofthe corruformed by end sectons of the plate that merge into saidextensions and which form continuations of the portions of the side walllocated between the corrugations, and welded joints between theco-operating extensions at the ends of the corrugations and also betweenthe adjacent end sections of the form part of said rim.

JAMES J. MULLEN. FRANCIS M. STAMBAUGH.

ribs formed by bent or a plate that on the side portions of edge of saidsidewall V

